1. Field of the Disclosure
This disclosure relates to low temperature cooling devices. Particularly, this disclosure relates to a cryogenic apparatus having a motor and method for using the motor for providing rotational freedom and movement to a mounted sample attached to a cold finger in a cryogenic cooler.
2. Description of the Related Art
Cryogen-free refrigerators, also called cryo-coolers or cryostats, utilize a closed-cycle circulating refrigerant (often helium gas) to extract heat from a cold finger at cryogenic temperatures and pump it away to a heat exchanger. The cold finger is a metallic heat sink which is actively cooled by the refrigerant. The cold finger can be temperature controlled and serves as a mounting point for an object. The main goal of attaching the object to the cold finger is that the object will be cooled, so that a user can use or make measurements on a cold sample. Objects to be cooled can include semiconductor devices, detectors, mechanisms, material samples, or any other objects that require fixed, cryogenic temperature operation.
In conventional cryo-coolers, measurements on mounted samples using a laser are performed by movement of a laser beam on a stationary object. However, this method has drawbacks, such as difficult alignment of optical beams. An ideal solution to this problem would be to keep the laser motionless, while rotating the mounted sample that is kept in thermal communication with its cryogenic surroundings.
In order to provide rotational freedom and movement to a mounted sample attached to a cold finger in a cryogenic cooler, the present disclosure describes a miniature cryogenic motor added inside a cryogenic apparatus such as a gas exchange box (GXB) for spinning a sample and thermally maintaining it at cryogenic temperatures.